The Complexity of Monadic Second-Order Unification
نویسندگان
چکیده
Monadic second-order unification is second-order unification where all function constants occurring in the equations are unary. Here we prove that the problem of deciding whether a set of monadic equations has a unifier is NP-complete, where we use the technique of compressing solutions using singleton context-free grammars. We prove that monadic second-order matching is also NP-complete.
منابع مشابه
Monadic Second-Order Unification Is NP-Complete
Monadic Second-Order Unification (MSOU) is Second-Order Unification where all function constants occurring in the equations are unary. Here we prove that the problem of deciding whether a set of monadic equations has a unifier is NP-complete. We also prove that Monadic Second-Order Matching is also NP-complete.
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ورودعنوان ژورنال:
- SIAM J. Comput.
دوره 38 شماره
صفحات -
تاریخ انتشار 2008